Hollow slab beam coarse aggregate UHPC hinge joint connecting structure
By using the design of rough aggregate UHPC and reinforced components in the hinge joint connection structure of the hollow plate beam, the problem of the existing hinge joint structure is easy to crack under multiple stress state, which significantly improves the shear strength and overall performance, and avoids avoidance. After the power of the board, the safety and durability of the bridge is improved.
Patent Information
- Application Number
- CN202420908189.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-28
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-04-28
AI Technical Summary
The existing hinge joint structure is prone to concrete cracking under multiple stress conditions, and the reinforced mesh has the problem of difficulty in vibrating the lower concrete, resulting in insufficient shear resistance of the bridge structure and prone to stress on veneers.
Using a hollow plate beam and coarse aggregate UHPC hinge joint connection structure, set up steel components in the connection channel, and design through the arc -shaped bond groove and bottom grouting seam to enhance the bonding strength and shear strength of the hinge joints to reduce the bottom grouting channel of the bottom grouting channel Space to improve the overallness and security of the structure.
It significantly improves the shear strength and delay of the interface destruction, enhance the construction quality and overall performance of the hinge seam, avoids the stress of the single board, and improves the safety and durability of the bridge.
Smart Images
Figure CN222412591U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of bridges, in particular to a hollow slab beam coarse aggregate UHPC hinged joint connection structure. Background Art
[0002] Prefabricated concrete hollow slab bridges are widely used in the construction of highways and urban bridges due to their standardized design, assembled construction, low building height and clear structural stress. The transverse connection between prefabricated concrete hollow slabs mainly relies on the hinged joints cast on site, and under the action of vehicle loads, the hinged joints are mainly subjected to shear force.
[0003] In the actual operation of bridges, the disease caused by insufficient shear resistance of hinged joints is one of the main diseases of this type of bridge. The disease is specifically manifested as longitudinal cracking of the bridge deck along the hinged joint, water seepage, and hollow slab misalignment. In extreme cases, the hollow slab may even break due to "single slab stress", which greatly affects the safety and durability of the bridge.
[0004] Hinge failure is the fundamental reason for the stress on the single plate of the bridge structure. Common situations include the following:
[0005] (1) During the construction design, it is easy to cause bearing support errors, which will increase the local bearing pressure. Under the action of repeated loads, the beam and slab will produce large displacement vibration and distortion, which will first affect the performance of the bridge; secondly, the repeated deformation of the beam and slab will accelerate the damage of the hinge joint, weaken the lateral transmission of internal forces between the upper beam and slab, and increase the load borne by the upper beam and slab, thus resulting in a single beam being stressed, which will have an adverse effect on the beam and slab.
[0006] (2) When a heavy vehicle passes, the hollow slab separated from the main body will deflect greatly, forming a step. In the elastic stage, after the vehicle leaves, the step can be restored. However, as the disease time increases, plastic deformation occurs, forming a permanent step.
[0007] (3) Corrosive ions penetrate into the structure, causing corrosion of the steel bars in the hinge joint and damage to the concrete, and rust marks appear at the bottom of the hinge joint. Long-term corrosion will cause the concrete in the hinge joint to loosen, peel off, and break. It may also cause the structural steel bars in the hinge joint to break, the structure to be completely destroyed, and the concrete in the connecting part to fail.
[0008] In view of the above problems: the existing hinged joint structure design is mainly carried out for a single problem, and it is not possible to solve multiple problems with one structure. For example, the common hinged joint structures currently include the following forms:
[0009] (1) Small joint form and steel plate connection: In theory, it meets the shear resistance structure of hinged joint, but in actual engineering, the shear resistance capacity is relatively small.
[0010] (2) The form of connecting steel bars in large hinged joints: The concrete in the hinged joints can be fully vibrated, and the quality of the concrete and the bonding with the beam body are more fully guaranteed. However, the shear resistance of the local connection between the hollow slab beam bridge and the hinged joint is often insufficient, resulting in cracks, and eventually forming a single slab stress situation.
[0011] (3) UHPC grouting material: UHPC itself is expensive, and the large amount of cementitious material inside it causes large shrinkage, which affects the direct bonding with the hollow slab beam and decouples the overall performance.
[0012] When the external load of the above-mentioned common hinged joint structures continues to increase, the connection interface is prone to crack from the bottom and expand upward along the joint surface, eventually forming a series of problems such as longitudinal cracks in the bridge deck, concrete peeling, cracking and leakage between bridge decks, and deformation of the bridge deck pavement. Specifically: (1) In the actual construction process, construction workers do not pay enough attention to the joints, and the small amount of concrete pouring also makes it difficult to ensure the quality of concrete. Often, the actual measured strength of the joint concrete does not meet the design requirements. Moreover, due to the limited space inside the small joints, the concrete cannot be fully vibrated and can only be rammed, which further deteriorates the quality of the concrete hinged joints; (2) Although the form of adding steel bars inside the large hinged joints strengthens the vibration of the concrete and the contact area between the hinged joints and the hollow slab beams, the larger the amount of concrete that needs to be poured in the large hinged joints, the greater the possibility of insufficient overall performance and shear strength of the connection between the hollow slab beam and the hinged joint, and the lower the safety performance; (3) Conventional UHPC has the characteristics of high cost and a large amount of cementitious materials inside, which leads to large shrinkage deformation. Shrinkage deformation will reduce the bonding performance of the interface between the new and old concrete, thereby reducing the integrity and shear resistance of the structure, which is not conducive to the stress of the hinged joint. Utility Model Content
[0013] In order to overcome at least one defect in the above-mentioned prior art, the utility model provides a hollow slab beam coarse aggregate UHPC hinged joint connection structure, which can solve the problem that the concrete in the bottom triangular connection area between the traditional hinged joint structure and the hollow slab beam undergoes concrete cracking under multiple stress states such as longitudinal tensile stress, transverse tensile stress, and vertical shear stress; and the presence of the steel mesh makes it difficult to vibrate and fill the lower concrete.
[0014] The utility model provides a hollow slab beam coarse aggregate UHPC hinged joint connection structure: a grouting material is cast in a connection channel between two adjacent hollow slab beams to form a connection body, so as to realize the connection of the two adjacent hollow slab beams, and is characterized in that: the upper parts of the two hollow slab beams at opposite ends are each provided with an inner groove, the two inner grooves form the connection channel, the lower bottom surface of each inner groove is a horizontal supporting surface, so as to form a supporting platform for supporting the connection body, the side walls of the inner groove are provided with a plurality of key grooves distributed at intervals along the vertical direction, a gap is left between the lower parts of the two hollow slab beams at opposite ends, so as to form a slender bottom grouting seam connected to the connection channel, a steel bar assembly is provided in the connection channel, the two ends of the steel bar assembly are respectively connected to one end of the two hollow slab beams, and the steel bar assembly is buried in the connection body.
[0015] Compared with the prior art, the hollow slab beam coarse aggregate UHPC hinged joint connection structure of the utility model has the following advantages:
[0016] First, the joint structure is simple. The arc-shaped keyways formed on the side walls of the inner grooves on both sides of the connecting channel not only increase the contact area between the hinge joint and the hollow slab beam, but also enhance the bonding strength of the hinge joint structure, further forming an aggregate interlocking effect with the coarse aggregate UHPC, which can significantly improve the interface shear strength and increase the slip amount, making the interface failure ductile. The shear strength of the keyway and the hinge joint increases with the increase in the number of keyways.
[0017] Secondly, a support platform is formed at the bottom of the connecting channel, which can facilitate the pouring and vibration of the joint concrete, better ensure the construction quality of the joint concrete, and eliminate the problem of poor bonding in the bottom area; the vertical shear stress generated by the gravity above the hinged joint is borne by the lower support platform, reducing the influence of the hinged joint on the arc-shaped keyway, improving the utilization rate of the arc-shaped hinged joint and facilitating construction; at the same time, the hinged joint reinforcement is more convenient and simple.
[0018] On the other hand, a steel bar assembly is provided in the connection channel for being buried in the connection body, and both ends of the steel bar assembly are respectively connected and fixed to two adjacent hollow slab beams, thereby more effectively improving the strength performance of the connection structure.
[0019] On the other hand, there is a vertical bottom grouting joint at the bottom. The cracking of the hinged joint starts at the bottom and continues to extend upward until the single plate is stressed. Since there is no stress-bearing steel bar at the bottom, the tensile and shear strengths are weaker than those in the lower area. Therefore, the bottom grouting joint takes up less space and has less gravity, so the additional shear force on the lower area is smaller. Therefore, by reducing the space of the bottom grouting channel to reduce the amount of coarse aggregate UHPC at the bottom, and relying on the integrity of the hollow slab beam to resist the stress, the safety of the hinged joint will be higher.
[0020] As an improvement, the top of each inner groove is provided with a guiding inclined surface, so that the top of the connecting channel forms a grouting portion with a larger opening at the top and a smaller opening at the bottom. In the above improved structure, the inclined structure with a larger opening at the top and a smaller opening at the bottom makes it easier for the grouting material to slide into the hinge joint.
[0021] As a further improvement, the side walls of the inner groove are inclined side walls that gradually incline inwards from top to bottom.
[0022] Furthermore, the steel bar assembly includes a first steel bar and a second steel bar, and a pavement layer is provided on the top surface of the hollow slab beam and the connecting body. The first steel bar extends transversely along the pavement layer, and is bent at both ends and vertically extended and inserted into the two hollow slab beams respectively; the second steel bar extends transversely along the supporting platform, and is bent at both ends and connected to the two hollow slab beams in an inclined direction respectively. In the above structure, the first steel bar can strengthen the transverse connection between the upper ends of the two hollow slab beams, and after being connected with the pavement layer, it can strengthen the joint force of the paving concrete and the beam body, thereby improving the structural strength. In addition, the second steel bar arranged at the lower end of the connecting channel is not only used to increase the force performance of the connecting body, but also used to strengthen the connection between the lower ends of the two adjacent hollow slab beams, so that the two adjacent hollow slab beams can better bear the force at the same time, avoiding the force of a single plate, thereby strengthening the bearing effect.
[0023] In a further improvement, a pre-embedded steel bar is pre-embedded at the lower end of the inner groove on the hollow slab beam, one end of the pre-embedded steel bar is pre-embedded in the hollow slab beam in an inclined manner, and the other end extends horizontally along the support surface; when two adjacent hollow slab beams are assembled, the pre-embedded steel bars on both sides are welded and fixed to form the second steel bar. In the above improved structure, the third steel bar is welded from two sections of pre-embedded steel bars, which has a simple structure, is easy to construct, and has high structural strength.
[0024] Furthermore, the steel bar assembly includes a third steel bar, which is formed by bending and crossing the same steel bar body, including a closed end and an open end, the open end extends upward into the pavement layer and is welded and fixed to the horizontal section of the first steel bar, and the open ends are bent to both sides along the transverse direction to be parallel to the pavement layer; the closed end is triangular in shape and located at the lower end of the connection body and above the second steel bar. In this structure, the third steel bar further enhances the strength of the connection body, and can transmit the force to the pavement structure through the upper open end.
[0025] Furthermore, a fourth steel bar extending longitudinally along the support platform is arranged in the closed end and at the two bottom corners of the triangle, and the fourth steel bar is tied and fixed to the horizontal section of the closed end of the third steel bar. In this structure, the fourth steel bar arranged longitudinally is tied and connected to the closed ends of the second and third steel bars, so that the whole can be placed in the connection channel during construction, which improves efficiency.
[0026] Preferably, the grouting material is a coarse aggregate UHPC slurry formed by mixing coarse aggregate, fine aggregate, cement, water and steel fiber. Traditional UHPC slurry has properties such as high strength, strong bonding force and corrosion resistance; but its cost price is relatively high, and its own cementitious materials often lead to large self-shrinkage deformation. The addition of coarse aggregate can reduce the cost of grouting materials by nearly half, reduce the proportion of cementitious materials, and reduce self-shrinkage deformation; the presence of coarse aggregate can form a chain effect with the keyway, effectively preventing the hinge joint from slipping.
[0027] Other improved features and advantages of the utility model will be described in the subsequent specific embodiments, and partly become apparent from the description, or understood by implementing the utility model. The purpose and other advantages of the utility model can be achieved and obtained through the structures specifically pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 This is a three-dimensional structural diagram of the hollow slab beam coarse aggregate UHPC hinged joint connection structure assembly of the utility model;
[0029] Figure 2 This is a diagram showing the state of two hollow slab beams approaching each other in the utility model;
[0030] Figure 3 This is a structural diagram of the connecting body in the utility model;
[0031] Figure 4 This is a partial structural diagram of a steel bar assembly installed in a connecting channel in the utility model.
[0032] Description of reference numerals:
[0033] 1. Hollow slab beam; 2. Connecting channel; 3. Connecting body; 4. Inner groove; 5. Support surface; 6. Arc keyway; 7. Bottom grouting joint; 8. Guide slope; 9. First steel bar; 10. Second steel bar; 11. Pavement layer; 12. Third steel bar; 13. Fourth steel bar; 14. Channel; 15. Raised structure. DETAILED DESCRIPTION
[0034] First, those skilled in the art should understand that these implementations are only used to explain the technical principles of the embodiments of the present application, and are not intended to limit the protection scope of the embodiments of the present application. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.
[0035] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "fixed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.
[0036] In the embodiments of the present application, unless otherwise clearly specified and limited, the first feature at the "upper end" or "lower end" of the second feature may be such that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium.
[0037] The present application is further described in detail below with reference to the accompanying drawings and specific embodiments.
[0038] See also Figure 1 to Figure 4 As shown, the embodiment of the present application discloses a coarse aggregate UHPC hinged joint connection structure of a hollow slab beam 1, in which a grouting material is cast in a connection channel 2 between two adjacent hollow slab beams 1 to form a connection body 3, so as to realize the connection of the two adjacent hollow slab beams 1, and the upper parts of the two hollow slab beams 1 at opposite ends are provided with inner grooves 4, and the two inner grooves 4 form a connection channel 2, and the lower bottom surface of each inner groove 4 is a horizontal support surface 5 to form a support platform for supporting the connection body 3; the side walls of the inner grooves 4 are concavely provided with a plurality of key grooves distributed at intervals along the vertical direction, and a gap is left between the lower parts of the opposite ends of the two hollow slab beams 1 to form a slender bottom grouting seam 7 connected to the connection channel 2, and a steel bar assembly is provided in the connection channel 2, and the two ends of the steel bar assembly are respectively connected to one end of the two hollow slab beams 1, and the steel bar assembly is buried in the connection body 3.
[0039] In practical applications, a corresponding pavement layer 11 is also required to be provided on the top surface of the hollow slab beam 1 and the connection body 3 as a bridge deck, and the pavement layer 11 is also a concrete casting structure.
[0040] In this embodiment, the grouting material is a coarse aggregate UHPC slurry formed by mixing coarse aggregate, fine aggregate, cement, water and steel fiber. Traditional UHPC slurry has properties such as high strength, strong bonding force and corrosion resistance; but its cost price is relatively high, and its own cementitious materials lead to large self-shrinkage deformation. The addition of coarse aggregate can reduce the cost of grouting materials by nearly half, reduce the proportion of cementitious materials, and reduce self-shrinkage deformation; the presence of coarse aggregate can form a chain effect with the keyway to effectively prevent the hinge joint from slipping.
[0041] In addition, the top of each inner groove 4 is provided with a guide slope 8, so that the top of the connecting channel 2 forms a grouting part with a larger opening at the top and a smaller opening at the bottom, and the inclination angle is a 45° structure, so as to facilitate the coarse aggregate UHPC grouting material to slide into the hinge joint. The inclined grouting part in this structure allows the upper sides of the final formed connection body 3 to form a convex structure with a triangular cross-section, so that the connection body 3 can bear more weight in the vertical direction. In addition, the side walls of the inner groove 4 in this structure are inclined side walls that gradually incline inward from top to bottom.
[0042] In this embodiment, see the attached Figure 4 The steel bar assembly mainly includes four types of steel bars, namely the first steel bar 9, the second steel bar 10, the third steel bar 12 and the fourth steel bar 13, which are used to improve the shear and tensile strength of the hinged joint. The first steel bar 9 extends horizontally along the pavement layer 11, and the two ends are bent and vertically extended to be inserted into the reserved channels 14 of the two hollow slab beams 1; it is the shear steel bar on the hinge of the hollow slab beam 1, which can enhance the lateral connection between the two slabs, and after being connected to the pavement layer 11, it can enhance the joint force of the paving concrete and the beam body.
[0043] The second steel bar 10 extends transversely along the support platform, and the two ends are bent and inserted into the reserved channels 14 on the two hollow slab beams 1 along the inclined direction. Here, the two ends of the second steel bar 10 extend downward at a 45° angle and are inserted into the two hollow slab beams 1; the second steel bar 10 is a hinged shear steel bar. The role of the second steel bar 10 here is not only as a force-bearing steel bar in the joint, but also a reinforcement measure for the transverse connection of adjacent hollow slab beams 1 at the bottom of the hollow slab beam 1. In this embodiment, the third steel bar 12 is welded by two separate sections of embedded steel bars. Specifically, embedded steel bars are pre-embedded at the lower end of the inner groove 4 of each hollow slab beam 1. Since the hollow slab beam 1 is also a prefabricated part, the embedded steel bars are directly set at the lower end of the inner groove 4 during its prefabrication process, wherein one end of the embedded steel bar is pre-embedded in the hollow slab beam 1 in an inclined manner, and the other end extends horizontally along the support surface 5, and the horizontal section of the embedded steel bar is set close to the support surface 5. This structure is more convenient for assembling the adjacent hollow slab beams 1 and has high structural strength.
[0044] In addition, see the attached Figure 4The third steel bar 12 is formed by bending and crossing the same steel bar body, including a closed end and an open end. The open end extends upward into the pavement layer 11 and is welded and fixed to the horizontal section of the first steel bar 9, and the open ends are bent to both sides in the transverse direction to be parallel to the pavement layer 11; the closed end is in a triangular shape and is located at the lower end of the connecting body 3 and above the second steel bar 10. In addition, in this structure, a fourth steel bar 13 extending longitudinally along the support platform is provided in the closed end and at the two bottom corners of the triangle, and the fourth steel bar 13 is tied and fixed to the horizontal section of the closed end of the third steel bar 12.
[0045] Here, the second steel bar 10, the third steel bar 12 and the fourth steel bar 13 work together as a whole to improve the tensile and bending resistance inside the hinged joint structure. The third steel bar 12 is formed by bending and crossing a steel bar, and the fourth steel bar 13 is tied and fixed to the corresponding position of the third steel bar 12 in the longitudinal direction to form a whole, which is convenient for construction and can form a hoop effect on the hinged joint coarse aggregate UHPC to a certain extent, thereby improving the overall stress performance of the joint concrete. The fourth steel bar 13 is mainly used to bear the tensile stress at the bottom of the joint to avoid the bottom coarse aggregate UHPC from being insufficiently tensile and cracking, which ultimately leads to the stress of the single plate.
[0046] The construction process of the utility model is as follows: there are a number of prefabricated hollow slab beams 1 at the construction site, and two adjacent hollow slab beams 1 are connected by using cast-in-place coarse aggregate UHPC to obtain a final connection body 3 as a hinged joint structure. The specific process is as follows: first, the required arc keyway 6 is preset on the side wall of the inner groove 4 of the hollow slab beam 1 according to the hinged joint structure, and then the corresponding position on the top surface of the hollow slab beam 1 is ensured to leave the hole 14 required for the insertion of the first steel bar 9, and the second steel bar 10 is embedded in sections. For the prefabricated hollow slab beam 1, it is also necessary to perform roughening treatment, and the rough surface with a concave and convex surface of not less than 6mm is required; the first steel bar 9 is inserted into the hole and grouting is performed in the insertion hole. After it is stable, the embedded steel bars on both sides are welded and connected, and the third steel bar 12 and the fourth longitudinal bar are first tied on the outside to form a hoop effect, and the third steel bar 12 and the fourth longitudinal bar are formed into a whole and placed together in the interior of the hinged joint structure; the open end of the third steel bar 12 and the first steel bar 9 are welded; after the steel bars are arranged, grouting is performed, and coarse aggregate UHPC is used for internal grouting. After the coarse aggregate UHPC is stable, the casting of the hinged joint structure is completed.
[0047] In the description of the present application, the description with reference to the terms "present embodiment", "some embodiments", etc. means that the specific features, mechanisms, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradicting each other.
[0048] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.
Claims
1. A hollow slab beam (1) coarse aggregate UHPC hinged joint connection structure, wherein a grouting material is used to cast a connection body (3) in a connection channel (2) between two adjacent hollow slab beams (1) to achieve connection of the two adjacent hollow slab beams (1), characterized in that: An inner groove (4) is provided at the upper part of the opposite ends of the two hollow slab beams (1), and the two inner grooves (4) form the connecting channel (2). The lower bottom surface of each inner groove (4) is a horizontal supporting surface (5) to form a supporting platform for supporting the connecting body (3). The side walls of the inner grooves (4) are provided with a plurality of arc-shaped key grooves (6) distributed at intervals in the vertical direction. A gap is left between the lower parts of the opposite ends of the two hollow slab beams (1) to form a slender bottom grouting joint (7) connected to the connecting channel (2). A steel bar assembly is provided in the connecting channel (2), and the two ends of the steel bar assembly are respectively connected to one end of the two hollow slab beams (1), and the steel bar assembly is buried in the connecting body (3).
2. The coarse aggregate UHPC hinged joint connection structure of the hollow slab beam (1) according to claim 1, characterized in that: The top of each inner groove (4) is provided with a guiding inclined surface (8), so that the top of the connecting channel (2) forms a grouting portion with a larger opening at the top and a smaller opening at the bottom.
3. The coarse aggregate UHPC hinged joint connection structure of the hollow slab beam (1) according to claim 1, characterized in that: The side wall of the inner groove (4) is an inclined side wall which gradually inclines inwards from top to bottom.
4. The coarse aggregate UHPC hinged joint connection structure of the hollow slab beam (1) according to claim 1, characterized in that: The steel bar assembly comprises a first steel bar (9) and a second steel bar (10); a pavement layer (11) is provided on the top surface of the hollow slab beam (1) and the connecting body (3); the first steel bar (9) extends transversely along the pavement layer (11), and is bent at both ends and extends vertically to be inserted into the two hollow slab beams (1); the second steel bar (10) extends transversely along the supporting platform, and is bent at both ends and connected to the two hollow slab beams (1) in an inclined direction.
5. The coarse aggregate UHPC hinged joint connection structure of the hollow slab beam (1) according to claim 4, characterized in that: An embedded steel bar is pre-embedded at the lower end of the inner groove (4) on the hollow slab beam (1), one end of the embedded steel bar is obliquely embedded in the hollow slab beam (1), and the other end extends horizontally along the support surface (5); when two adjacent hollow slab beams (1) are assembled, the embedded steel bars on both sides are welded and fixed to form the second steel bar (10).
6. The coarse aggregate UHPC hinged joint connection structure of the hollow slab beam (1) according to claim 4, characterized in that: The steel bar assembly comprises a third steel bar (12), the third steel bar (12) being formed by bending and crossing the same steel bar body, and comprising a closed end and an open end, the open end extending upward into the pavement layer (11) and being welded and fixed to the horizontal section of the first steel bar (9), and the open end being bent transversely to both sides to be parallel to the pavement layer (11); the closed end is triangular in shape and is located at the lower end of the connecting body (3) and above the second steel bar (10).
7. The coarse aggregate UHPC hinged joint connection structure of the hollow slab beam (1) according to claim 6, characterized in that: A fourth steel bar (13) extending longitudinally along the support platform is arranged inside the closed end and at the two bottom corners of the triangle, and the fourth steel bar (13) is tied and fixed to the horizontal section of the closed end of the third steel bar (12).
8. The coarse aggregate UHPC hinged joint connection structure of the hollow slab beam (1) according to any one of claims 1 to 7, characterized in that: The grouting material is a coarse aggregate UHPC slurry formed by mixing coarse aggregate, fine aggregate, cement, water and steel fiber.